DE10248351A1 - Electrically driven camshaft adjuster - Google Patents

Abstract

The invention relates to a camshaft adjuster (1) for adjusting and fixing the relative angular position of a camshaft (8) with respect to the crankshaft of a reciprocating piston internal combustion engine, with a high-ratio and low-friction adjusting gear (2) that a drive shaft connected to the crankshaft in a rotationally fixed manner, one with the camshaft (8) non-rotatably connected output shaft and an adjusting shaft (9) connected to an adjusting motor shaft (10) of an adjusting motor. DOLLAR A An inexpensive to operate camshaft adjuster (1) is achieved in that the adjustment gear (2) and the adjustment motor (3) are designed as separate units and are connected to each other by a coupling (4) that is free of rotational play and can be released.

Description

Field of the Invention

The invention relates to a camshaft adjuster for adjusting and fixing the angular position of the camshaft Crankshaft of a reciprocating internal combustion engine, especially after the preamble of claim 1.

background the invention

In the DE 41 10 195 A1 discloses a camshaft adjuster for adjusting and fixing the relative rotational angle position of a camshaft relative to the crankshaft of a reciprocating piston internal combustion engine, with a high-ratio and low-friction adjusting gear, which has an input shaft which is fixedly connected to the crankshaft, an output shaft which is connected in a rotationally fixed manner to the camshaft, and one with an adjusting motor shaft of an adjusting motor connected adjustment shaft.

In this solution, the servomotor shaft is integral with the adjustment shaft of the adjustment gear. This means in the event of the adjustment motor failing, the entire camshaft adjuster should always be replaced become. Moreover the assembly of the same is complex because a pre-assembly of the complete Variable motor not possible is.

Task of invention

The invention is based on the object to create a camshaft adjuster that is inexpensive too operate.

Summary the invention

According to the invention, the object is achieved by Characteristics of the independent Claim 1 solved. Due to the separate design of the adjustment motor and adjustment gear the actuator can be completely pre-assembled and due to the detachable coupling can be easily installed or replaced. Through the The coupling is free from torsional backlash because of its low-wear and low-noise operation guaranteed.

The arrangement according to the invention of a releasable coupling between adjustment gear and adjustment motor is independent of the type of actuator. The electrical one is particularly suitable Adjusting. This has opposite the advantage of a hydraulic motor, regardless of the speed of the internal combustion engine and thus to function even when it is at a standstill. Also has the oil viscosity has no effect on its function. Across from the pneumatic actuator has the advantage of a pneumatic motor the power supply that is normally present anyway and the more uncomplicated one Controllability.

It offers manufacturing and therefore cost advantages, if the coupling is two joinable Has parts, one of which with the servomotor shaft, the another is rotatably connected to the adjusting shaft.

A simple assembly of the adjustment motor is achieved in that one of the two parts as the outer part, the other is designed as an inner part, the two parts can be inserted into one another without any play.

An advantageous development of Invention is that the coupling as a profile shaft coupling, is preferably designed as a double-shaft coupling, each two coupling surfaces on the outer part and two coupling surfaces each has on the inner part, the latter preferably preventing rotational play Have means. The proven Two-sided shaft coupling offers enough space for accommodation of torque transmitting and anti-spinning means. Keyways also come as couplings and profile shaft couplings such as polygon, tooth, spline and polygonal shaft couplings in question. Also a shaft milled on one side with a corresponding one counterpart (similar the square, but only with a straight surface) is also conceivable. The application of the anti-spinning means on the inner part offers advantages in terms of assembly and installation space compared to their possible installation on the outer part.

A conventional solution is to be seen in the fact that a minimal, tight tolerance between the coupling surfaces of the inner and outer part is provided. The manufacturing precision required for this is necessary a corresponding construction effort.

A cheaper solution is that as pre-tensioned metal or plastic springs are provided that bridge the game between the coupling surfaces. Because of the preload of the springs and their sufficient travel the play between the coupling surfaces and its tolerance are chosen to be relatively large, whereby the construction effort is reduced accordingly.

The advantage is that the metal springs preferably as flat bending or disc springs and the plastic spring preferably designed as a polymer tape or as a polymer O-ring and preferably in grooves or in a circumferential groove of the coupling surfaces of the Are arranged inside. The attachment of the polymer springs in Ring grooves in the coupling surfaces of the inner part especially facilitates the assembly of the polymer tape and the polymer O-ring, which are arranged there captively.

The spring and assembly forces required for torque transmission and avoidance of torsional play are relatively low, since the torque to be transmitted of less than 1 Nm is relatively low, so that with a corresponding spring stiffness there is no relative rotation of the electric motor and the adjusting shaft. The feathers can also make small ones Misalignment of these waves can be compensated. It has advantages if the flat bending or disc springs are designed as a one-piece spring clip, which preferably snaps into corners of the inner part. In this way, the flat bending or disc springs in pairs form a unit that is captively attached to the inner part and thus facilitates the assembly of the adjustment motor.

An advantageous training of Invention is that the coupling as a tubular shaft coupling is formed, with a hollow cylindrical outer part and a coaxial, cylindrical inner part, which is arranged with play in the outer part and preferably has the rotational play-avoiding means. The two Parts are designed as turned parts that are simple and inexpensive to use are finished. It is also an advantage that as a backlash-avoiding Means an elastically deformable tolerance ring, preferably made of Metal is provided in a radial groove, preferably on the circumference of the coaxial, cylindrical inner part is arranged and this protrudes radially by a certain amount. in principle could the tolerance ring can also be arranged on the inner circumference of the outer part, however is the arrangement according to the invention easy to assemble.

The protrusion of the tolerance sleeve creates during assembly, a resilient deformation of the same to a non-positive Connection between the inner and outer part leads. When choosing the supernatant care must be taken to ensure that the torque of the servomotor is transferable is without the axial movement of the inner and outer part to each other and thus the thermal expansion to hinder significantly. The tolerance ring is also a polymer ring conceivable.

Through advantageous training The invention achieves that as a rotation-avoiding means at least one locking ball or a preferably cylindrical locking pin are provided with a tapered end, which are in radial or Through holes preferably of the coaxial, cylindrical inner part led with game and in alignment with these other, smaller radial bores in the hollow cylindrical outer part under the force of a compression or through spring by one by the smaller diameter limited dimension are displaceable. Instead of one can also advantageously two or more locking balls or cylindrical Kick locking pins. These could also be in the outer part be arranged and radially in a corresponding bore of the inner part intervention. Alternatively to the cylindrical pins, too those with, for example, square or rectangular or also any other cross-section can be used. This one too Variant can small misalignment between the adjusting motor and adjusting shaft be balanced. The through hole has compared to the two radial bores, which it replaces, the advantage simpler Manufacturing and even pressurization the locking balls or locking pins.

By appropriate interpretation of the Spring force of the compression or through springs and / or the cone angle of the cylindrical pins, the transmissible torque is the Pipe coupling can be limited. This then acts as a safety clutch, by overload the locking balls or the cylindrical locking pins against the relative low spring forces from the holes in the outer part repressed and so the two waves are decoupled. For an axial mobility of the with locking balls or tubular shaft coupling equipped with cylindrical locking pins it is necessary that the other radial bores than in axial Elongated holes are trained.

It is beneficial if the clutch is designed as a claw coupling, the two parts of the same Have axial claws arranged in diameter, which interlock, with gaps between the claws are provided by an elastic, prestressed by tooth elements Polymer ring are bridged without rotational play. The claw coupling enables due to the elasticity of the polymer rim also compensates for a slight misalignment. Moreover it has a vibration-dampening effect.

Another advantageous clutch is as a profile shaft coupling, preferably as a toothed shaft coupling, trained, the inner or outer part, especially their Internal or external toothing, off elastic plastic is formed. Given the relative low to be transferred Torques are various couplings, for example polygon or Polygonal shaft couplings, suitable for half-sided execution in plastic. The splined shaft coupling is particularly easy to assemble out. Also enables the compensation due to the elastic plastic ring gear a slight misalignment. It also has a vibration-dampening effect the internal damping of the Plastic.

For a rational production and for a compact design, it is advantageous that the plastic existing internal or external gearing directly on corresponding parts of the splined shaft coupling or on one appropriately trained metallic intermediate sleeve are vulcanized and that the intermediate sleeve connected to the spline coupling preferably by a press fit is.

An advantageous embodiment of the invention consists in that the coupling is designed as a magnetic shaft coupling, the two parts of which have opposing permanent magnets which transmit the drive torque of the adjusting motor from the adjusting motor shaft to the adjusting shaft without contact and without backlash. The permanent magnets can be made of ferritic or rare earth material, such as samarium cobalt or neodymium iron boron. Because of the of the adjusting motor shaft to be transmitted to the adjusting shaft, the low torque is carried approximately synchronously by the magnetic force, that is to say without backlash. This clutch can also be designed as a safety clutch that slips when overloaded. Since it is a contactless coupling, the torque is transmitted with little vibration. A small axis offset can also be compensated for.

There are advantages to permanent magnets are preferably arranged axially and a non-magnetic between them Membrane with play on both sides is provided, which seals the adjusting motor in an oil-tight manner. at Axial arrangement of the magnets must be ensured that whose for the transfer of torque allowed Maximum distance not exceeded becomes. On the other hand, may the permanent magnets do not touch the membrane. The also possible radial In contrast, the arrangement of the magnets is against axial displacement largely insensitive, but the formation of a membrane between these permanent magnets more difficult.

Short description of the drawings

Further features of the invention result from the following description and the accompanying drawings, in which embodiments of the invention are shown schematically. Show it:

1 a camshaft adjuster with a separate electric adjusting motor and adjusting gear, which are detachably connected by a double-shaft coupling;

2 a two-sided shaft coupling according to detail X of 1 in cross section;

3 a longitudinal section through the square shaft coupling of 2 ;

4 a longitudinal section through a double shaft coupling similar 3 , but with torque transmitting and torsional backlash avoiding metal springs;

5 a cross section through the double-shaft coupling of 4 ;

6 a cross section through a double shaft coupling similar 5 , but with one-piece spring clip;

7 a longitudinal section through a double shaft coupling similar 4 , but with a ribbon as a polymer spring;

8th a longitudinal section through a double shaft coupling similar 7 , but with an O-ring as a polymer spring;

9 a cross section XX through the double-shaft coupling of 7 and 8th ;

10 a cross section through a tubular shaft coupling with two opposite, spring-loaded locking balls in separate radial bores of a coaxial, cylindrical inner part;

11 a cross section through a tubular shaft coupling similar 10 , but with a radial through hole in which a through spring for the two locking balls is arranged;

12 a cross section through a tubular shaft coupling similar 10 , but with two cylindrical locking pins instead of the two locking balls;

13 a cross section through a tubular shaft coupling similar 11 , but with two cylindrical locking pins instead of the two locking balls;

14 a longitudinal section through a tubular shaft coupling, with a cylindrical inner part which has an annular groove on its outer circumference, in which there is an elastically deformable tolerance ring made of metal;

15 a partial longitudinal section through a claw coupling;

16 an axial view of the dog clutch of 15 ;

17 a view of an elastomer collar of the dog clutch of 15 and 16 ;

18 an axial view of an outer part of a spline coupling with an internal toothing made of plastic;

19 a partial longitudinal section of the outer part of 18 with the internal toothing made of plastic;

20 an axial view of one of the outer part of the 18 and 19 matching inner part with external teeth made of metal;

21 a side view of the inner part of 20 ;

22 a longitudinal section through a camshaft adjuster similar 1 , but with a magnetic shaft coupling instead of the double shaft coupling.

Full Description of the invention

In 1 is an electric camshaft adjuster 1 with an adjustment gear 2 and an electric actuator 3 shown, which are formed as separate units and are releasably connected by a clutch.

The variable speed gear 2 is a three-shaft gearbox which, as an eccentric gearbox, has a high reduction ratio (reduction range from 1:30 to 1: 250) and a high degree of efficiency. The variable speed gear 2 has a drive shaft, a drive shaft and an adjustment shaft 9 , The drive shaft is as a sprocket 5 formed and is in a rotationally fixed connection with a crankshaft, not shown, via a chain, also not shown. The output shaft is the end wall 6 executed by means of a clamping screw 7 non-rotatable with a camshaft 8th connected is. The adjustment shaft 9 is designed as an eccentric shaft that has a double-shaft coupling 4 with a servomotor shaft 10 practically without backlash, but axially ver is slidably connected. The adjustment shaft 9 serves to drive two spur gears 11 . 12 with an internal toothing 13 of the sprocket 5 Comb and the adjustment torque via pins 14 and over the end wall 6 on the camshaft 8th transfer. The electric actuator 3 has a stator 15 on the cylinder head 16 is attached and a permanent magnet rotor 17 that deals with the camshaft 8th rotates.

In the 2 and 3 is the two-sided shaft coupling designated as detail X. 4 the 1 shown enlarged in cross and longitudinal section. An inner part 18 the two-sided shaft coupling 4 is with the servomotor shaft 10 , an outer part 19 with the adjustment shaft 9 formed in one piece. Both parts 18 . 19 each have the same coupling surfaces 20 . 21 between which the minimum clearance required for axial displacement (thermal expansion, assembly) is provided. In this way, a minimal torsional backlash is achieved for the durability and low noise level of the double-edged shaft coupling which is subjected to alternating torques 4 important is. The one for the low clearance and tolerances on both parts 18 . 19 however, the manufacturing effort required is considerable.

This disadvantage is caused by a double-shaft coupling shown in longitudinal and cross-section 4 ' the 4 and 5 encountered. Here is in the clutch surfaces 20 ' of the inner parts 18 ' one groove each 22 provided, in which a flat bending or a plate spring 23 is used with preload. The feathers 23 bridge the now permissible, relatively large clearance between the inner and an outer part by the preload and the spring travel 18 ' . 19 ' and take over the transmission of the torque of the adjustment motor 3 , Since this is relatively low at <1 Nm, the spring and assembly forces required are also low and, with the appropriate spring stiffness, there is no twisting between the adjusting and adjusting motor shafts 9 . 10 on. Because the torque of the actuator 3 only about the feathers 23 is transmitted, the coupling surfaces touch 20 ' . 21 ' Of the parts 18 ' . 19 ' Not. The feathers 23 are in connection with the relatively large play between the coupling surfaces 20 ' . 21 ' able to make small axis misalignments between the adjusting and the adjusting motor shaft 9 . 10 compensate.

6 shows a clutch 4 ' as a variant of 4 and 5 , where the two feathers 23 and the grooves 22 of the inner part 18 ' through a spring clip 24 to a one-piece spring clip 25 are united at corners 26 of the inner part 18 ' snaps into place. This protection against loss means that installation is considerably easier.

In the 7 and 8th is a two-sided shaft coupling 4 ' in longitudinal section and in 9 shown in cross-section, instead of the flat bending or disc springs 23 a polymer tape 28 or a polymer O-ring 29 are provided. These are in a circumferential groove 30 . 31 of the inner parts 18 ' to their coupling surfaces 20 ' assembled with a protrusion so that they have a preload when installed. This means that there is also a lot of play between the coupling surfaces in this variant 20 ' . 21 ' of the inner and outer parts 18 ' . 19 ' bridged without touching. Again, the relatively low torque of the adjustment motor 3 with appropriate rigidity of the polymer tape 28 and the polymer O-ring 29 without relative rotation of the inner and outer parts 18 ' . 19 ' transfer.

In 9 is the circumferential groove 30 . 31 inside 18 ' with the polymer tape 28 and the polymer O-ring 29 to recognize the optimal bridging of play between the inner parts 18 ' and the outside parts 19 ' the clutch 4 ' cause.

The 10 to 13 show cross sections through a tubular shaft coupling 32 with a hollow cylindrical outer part 33 and a coaxial, cylindrical inner part 34 that with play in the hollow cylindrical outer part 33 is arranged.

In the cylindrical inner part 34 the 10 are two identical, aligned radial bores starting from its circumference 35 provided, each in a compression spring 36 is arranged. These act on one locking ball each 37 one that in the radial holes 35 are guided with play and displace them in a different radial bore 38 in the outer part 33 , The other radial holes 38 aligned in a certain rotational position of the cylindrical inner part 34 with the radial holes 35 , Due to a certain, smaller diameter of the other radial bores 38 compared to the radial bores 35 , penetrate the locking balls 37 only to a certain depth in the other radial bore 38 a, which is used to transmit the torque of the adjusting motor 3 sufficient. The locking balls carry on a trailing edge 43 the other radial bore 38 , By choosing the diameter of the other radial bore 38 the amount of torque that can be transmitted can be determined. In this way the tubular shaft coupling 32 for safety clutch.

In 11 are the two radial holes 35 through a through hole 39 with a through spring 40 replaced. This solution has compared to that of 10 the advantage of less construction work and an even pressure load on the two locking balls 37 , which allows a more precise definition of the transmissible torque.

The structure of the tubular shaft couplings 32 the 12 and 13 corresponds to that of 10 and 11 , The difference is in the use of cylindrical locking pins 41 instead of the locking balls 37 , with tapered ends 42 by means of the pressure force of the compression springs 36 ' or the through spring 40 ' in the through hole 39 in other radial bores 38 ' protrude and at their trailing edge 43 ' wear. In this variant, the transmissible torque can be adjusted via the size of the Ke angle of the tapered end 42 be limited. This also allows this tubular shaft coupling 32 serve as a safety clutch.

In 14 is a further coupling variant a tubular shaft coupling 32 ' shown. This is a non-positive torque transmission between a cylindrical inner part 34 ' and a hollow cylindrical outer part 33 ' through one in a radial groove 45 arranged, elastically deformable tolerance ring 44 made of metal. The tolerance ring 44 dominates the radial groove 45 by a certain amount, which determines the elastic deformation and the dependent adhesion.

In 15 is a partial cross section through a claw coupling 46 with claws 47 . 48 shown. These are at the free ends of the adjusting and adjusting motor shaft 9 . 10 non-rotatably arranged on the same diameter. They interlock with intervals that are separated by a 17 shown elastic, prestressed polymer ring 49 with tooth elements 50 are bridged without rotational play.

The 16 shows an axial view of the dog clutch 46 , with eight claws each 47 and 48 as well as the polymer wreath 49 with eight tooth segments 50 are shown in dashed lines. The claw coupling 46 equals small misalignments between the adjustment and the adjustment motor shaft 9 . 10 off, and also allows a small axial displacement between them.

In 18 is an axial view of an outer part 55 a splined shaft coupling with internal teeth 56 shown made of elastic plastic. The 19 shows a partial longitudinal section of the outer part 55 of 18 , The internal toothing 56 is in a radial groove 57 an intermediate sleeve 58 vulcanized. In radial extension is behind each tooth 59 a radial bore 60 provided that filled with the plastic and through a rivet-like cover 61 is completed. The one in the radial bore 60 Plastic increases the transferable torque of the internal toothing 56 , The intermediate sleeve 58 can be part of the adjustment shaft 9 or the servomotor shaft 10 serve or be pressed into this ..

The 20 and 21 show an inner part 62 made of metal with external teeth 63 who have favourited External Teeth 64 having. These are narrower than the inner teeth 59 made of plastic because they have a higher strength. The internal tooth gaps are corresponding 65 narrower than the external tooth gaps 66 , Basically, the external teeth could also 63 be formed in plastic. However, there is the internal toothing 56 because of the possible larger volume of material.

The 22 shows a camshaft adjuster 1' , its adjustment shaft 9 with the servomotor shaft 10 ' through a permanent magnet shaft coupling 51 are connected without contact and without play. At the free ends of the adjusting and adjusting motor shaft 9 . 10 ' are permanent magnets 52 . 53 attached, between which an unmagnetic membrane 54 that runs the actuator 3 oil-tight. In this way the actuator is 3 hermetically sealed without friction-generating sealing elements.

1, 1'

Phaser

2

variator

3

electrical adjusting

4, 4 ', 4 "

Two square shaft coupling

5

Sprocket

6

end wall

7

clamping screw

8th

camshaft

9

adjusting

10 10 '

adjusting motor

11

spur gear

12

spur gear

13

internal gearing

14

pen

15

stator

16

cylinder head

17

Permanent magnet rotor

18 18 '

inner part

19 19 '

outer part

20 20 '

coupling surface

21 21 '

coupling surface

22

groove

23

Flachbiege- or disc spring

24

spring clip

25

spring clip

26

corner

27

transverse groove

28

polymer tape

29

Polymer O-ring

30

encircling groove

31

encircling groove

32 32 '

Pipe shaft coupling

33 33 '

hollow cylindrical outer part

34 34 '

coaxial cylindrical inner part

35

radial bore

36 36 '

compression spring

37

detent ball

38 38 '

other radial bore

39

Through Hole

40 40 '

Through spring

41

cylindrical Plunger

42

conically tapered end

43 43 '

trailing edge

44

tolerance ring

45

radial groove

46

claw clutch

47

claw

48

claw

49

polymer wreath

50

tooth element

51

Permanent magnet shaft coupling

52

permanent magnet

53

permanent magnet

54

membrane

55

outer part

56

internal gearing

57

radial groove

58

intermediate sleeve

59

internal ring

60

radial bore

61

cover

62

inner part

63

external teeth

64

outdoor gear

65

Internal tooth gaps

66

Outer tooth gaps

Claims (18)

Camshaft adjuster ( 1 . 1' ) for adjusting and fixing the relative angle of rotation of a camshaft ( 8th ) compared to the crankshaft of a reciprocating piston internal combustion engine, with a high-ratio and low-friction adjustment gear ( 2 ) that a drive shaft connected to the crankshaft in a rotationally fixed manner, one with the camshaft ( 8th ) non-rotatably connected output shaft and one with a variable motor shaft ( 10 ) an adjustment shaft connected to an adjustment motor ( 9 ), characterized in that the adjustment gear ( 2 ) and the adjustment motor ( 3 ) formed as separate units and by a coupling that is free of rotational play and can be released ( 4 . 4 ' . 4 '; 32 . 32 '; 46 ; 51 ) are connected. Camshaft adjuster according to claim 1, characterized in that the adjusting motor is preferably an electric adjusting motor ( 3 ) is. Camshaft adjuster according to claim 2, characterized in that the clutch ( 4 . 4 ' . 4 '; 32 . 32 '; 46 . 51 ) has two parts that can be joined together, one of which is connected to the adjusting motor shaft ( 10 ) and the other with the adjustment shaft ( 9 ) non-rotatably connected or with the shafts ( 9 . 10 ) is formed in one piece. Camshaft adjuster according to claim 3, characterized in that one of the two parts as an outer part ( 19 . 19 '; 33 . 33 ' ) the other as an inner part ( 18 . 18 '; 34 . 34 ' ) is formed, wherein the two parts can be inserted into one another without rotational play. Camshaft adjuster according to claim 4, characterized in that the coupling as a profile shaft coupling, preferably as a double-shaft coupling ( 4 . 4 ' . 4 ' ) is designed, each with two coupling surfaces ( 21 . 21 ' ) on the outer part ( 19 . 19 ' ) and two coupling surfaces ( 20 . 20 ' ) on the inner part ( 18 . 18 ' ), wherein preferably means are provided on the latter to prevent rotational play. Camshaft adjuster according to Claim 5, characterized in that a minimal, closely tolerated play between the coupling surfaces ( 20 . 21 ) of the inner and outer part ( 18 . 19 ) is provided. Camshaft adjuster according to claim 5, characterized in that prestressed metal or plastic springs are provided as means for preventing backlash, which prevent the play between the coupling surfaces ( 20 ' . 21 ' ) bridge. Camshaft adjuster according to claim 7, characterized in that the metal springs are preferably as flat bending or disc springs ( 23 ) and the plastic springs preferably as a polymer tape ( 28 ) or as a polymer O-ring ( 29 ) trained and preferably in grooves ( 22 ) or a circumferential groove ( 30 . 31 ) the coupling surfaces ( 20 ' ) of the inner part ( 18 ' ) are arranged. Camshaft adjuster according to claim 8, characterized in that the flat bending or disc springs ( 23 ) as a one-piece spring clip ( 25 ) are formed, which are preferably at corners ( 26 ) of the inner part ( 18 ' ) snaps into place. Camshaft adjuster according to claim 4, characterized in that the coupling as a tubular shaft coupling ( 32 . 32 ' ) is designed with a hollow cylindrical outer part ( 33 . 33 ' ) and a coaxial, cylindrical inner part ( 34 . 34 ' ) with play in the outer part ( 33 . 33 ' ) is arranged and preferably has the rotational play-avoiding means. Camshaft adjuster according to claim 10, characterized in that an elastically deformable tolerance ring ( 44 ), preferably made of metal, which is provided in a radial groove ( 45 ) preferably on the circumference of the coaxial, cylindrical inner part ( 34 ' ) is arranged and this projects radially by a certain amount. Camshaft adjuster according to claim 10, characterized in that at least one locking ball ( 37 ) or a preferably cylindrical locking pin ( 41 ) with a tapered end ( 42 ) are provided, which are in radial or through bores ( 35 . 39 ) preferably the coaxial, cylindrical inner part ( 34 ) guided with play and in other radial holes aligned with these ( 38 . 38 ' ) smaller diameter in the hollow cylindrical outer part ( 33 ) under the force of a compression or through spring ( 36 . 36 '; 40 . 40 ' ) can be moved by a dimension limited by the smaller diameter. Camshaft adjuster according to claim 12, characterized in that the other radial bores ( 38 . 38 ' ) than in the axial direction directed elongated holes are formed. Camshaft adjuster according to claim 3, characterized in that the clutch as a dog clutch ( 46 ) is formed, the two parts of which are arranged on the same diameter, axial claws ( 47 . 48 ) which engage in one another, with the claws ( 47 . 48 ) Distances are provided, which by tooth elements ( 50 ) an elastic, pre-stressed polymer ring ( 49 ) are bridged without any play. Camshaft adjuster according to claim 4, characterized in that the coupling is designed as a profile shaft coupling, preferably as a toothed shaft coupling, the outer or inner part ( 55 . 65 ), especially their internal or external teeth ( 56 . 63 ) is made of elastic plastic. Camshaft adjuster according to claim 15, characterized in that the external toothing made of plastic ( 56 . 63 ) directly on corresponding parts of the splined shaft coupling or on a suitably designed, metallic intermediate sleeve ( 58 ) is preferably vulcanized and that the intermediate sleeve ( 58 ) is preferably connected to the spline coupling by a press fit. Camshaft adjuster according to claim 3, characterized in that the coupling as a magnetic shaft coupling ( 51 ) is formed, the two parts of which are opposite permanent magnets ( 52 . 53 ) which have the drive torque of the adjustment motor ( 3 ) contact-free and without backlash from the actuator motor shaft by magnetic forces ( 10 ' ) on the adjusting shaft ( 9 ) transfer. Camshaft adjuster according to claim 17, characterized in that the permanent magnets ( 52 . 53 ) are preferably arranged axially and the non-magnetic membrane between them ( 54 ) is provided with play on both sides, which the adjusting motor ( 3 ) seals oil-tight.